C:\Program Files\MySQL\MySQL Server 5.5\bin>net stop mysql 
//MySQL 服务正在停止. 
//MySQL 服务已成功停止。 

C:\Program Files\MySQL\MySQL Server 5.5\bin>mysql 
Welcome to the MySQL monitor. Commands end with ; or \g. 
Your MySQL connection id is 1 
Server version: 5.5.36 MySQL Community Server (GPL) 
  
Copyright (c) 2000, 2014, Oracle and/or its affiliates. All rights reserved. 
  
Oracle is a registered trademark of Oracle Corporation and/or its 
affiliates. Other names may be trademarks of their respective 
owners. 
  
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. 
  
mysql> show databases; 
+--------------------+ 
| Database      | 
+--------------------+ 
| information_schema | 
| mysql       | 
| performance_schema | 
| test        | 
+--------------------+ 
4 rows in set (0.00 sec) 

mysql> use mysql; 
Database changed 
mysql> update user set password=PASSWORD('root') where user='root'; 
Query OK, 2 rows affected (0.00 sec) 
Rows matched: 2 Changed: 2 Warnings: 0 
  
mysql> flush privileges; 
Query OK, 0 rows affected (0.01 sec) 

mysql> quit 
Bye 

C:\Program Files\MySQL\MySQL Server 5.5\bin>net start mysql 
//MySQL 服务正在启动 . 
//MySQL 服务已经启动成功。 

C:\Program Files\MySQL\MySQL Server 5.5\bin>mysql -u root -p root 
Welcome to the MySQL monitor. Commands end with ; or \g. 
Your MySQL connection id is 1 
Server version: 5.5.36 MySQL Community Server (GPL) 
  
Copyright (c) 2000, 2014, Oracle and/or its affiliates. All rights reserved. 
  
Oracle is a registered trademark of Oracle Corporation and/or its 
affiliates. Other names may be trademarks of their respective 
owners. 
  
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. 
  
mysql>